Electrically heated chair

ABSTRACT

An article of body-supporting furniture having an open frame and a receiving section connected to said frame to provide a seating area within the frame. The reclining section including a reclining, flexible heating surface having a layer of electrically conductive heating material, insulating layers enclosing said electrically conductive layer, and electrical contacts connected to said heating material for electrical connection to live voltage or a battery. The heating material having a positive temperature coefficient of electrical resistance to minimize voltage supply requirements and to provide current limitations.

United States Patent 72] Inventor Alfred Pohler Reutte, Austria [21]Appl. No. 867,122 4 [22] Filed Oct. 17, 1969 [45] Patented [73] AssigneeNov. 16, l 971 Schwarzkopf Development Corporation New York, N.Y.

[ 32] Priority Nov. 11, 1968 3 3] Austria [54] ELECTRICALLY HEATED CHAIR5 Claims, 4 Drawing Figs.

52 u.s.c1 219/217, 5 284, 128/377, 219/527, 219/536, 219/544,

[56] References Cited UNITED STATES PATENTS 2,559,077 7/1951 Johnson etal. 219/543 3,125,663 3/1964 Hoffman 219/217 3,375,774 4/1968 Fujimuraet al 219/441 X 692,554 2/1902 Stanger 128 377 2,299,162 10/1942 Marick219 527 2,735,926 2/1956 Langlois. 219/528 2,481,050 9/1949 Starnes297/180X 2,741,298 4/1956 Roberts.. 297/56x 3,017,493 1/1962 Cooke219/217x 3,060,303 10/1962 Skoglundetal. 219/549 3,385,959 5/1968Amesetal 219/549 3,400,254 9/1968 Takemori 219/549 3,448,246 6/1969Armbruster .1 219/528 FORElGN PATENTS 427,039 3/1926 Germany 219/2171,077,798 8/1967 0163113111111" 219/217 Primary Examiner- Volodymyr Y.Mayewsky Attorney-Morgan, Finnegan, Durham & Pine ABSTRACT: An articleof body-supporting furniture having an open frame and a receivingsection connected to said frame to provide a seating area within theframe. The reclining section including a reclining, flexible heatingsurface having a layer of electrically conductive heating material,insulating layers enclosing said electrically conductive layer, andelectrical contacts connected to said heating material for electricalconnection to live voltage or a battery. The heating material having apositive temperature coefficient of electrical resistance to minimizevoltage supply requirements and to provide current limitations.

This invention relates to electrically heated furniture and is describedin terms of a chair structure, more specifically a heated recliningchair.

The use of deck chairs in open air on sunny but cool days has thedisadvantage of exposing the body of the user to markedly differenttemperatures. It is an object of this invention to eliminate thatdisadvantage.

According to a further characteristic of the invention the heating ofthe reclining section is accomplished with a surface heat conductingunit which reduces only slightly the flexibility of the body supportingor reclining structure. The heating unit can be built integrally in thereclining surface, or the reclining surface can be treated to serve as aheat conductor.

Serving to illustrate the exemplary embodiments are the drawings ofwhich:

FIGS. 1 and 2 are isometric views which illustrate linebattery-energizedembodiments;

F IG. 3 is a plan schematic view of the and FIG. 4 is a sectionalschematic view through the reclining section on an enlarged scale.

H0. 1 shows a deck chair which except as noted hereinafter is ofcustomary construction. Assembled in the reclining section 1 is anelectrically heatable surface heating unit. On the bottom of the deckchair a socket 7 (FIG. 3) is attached, the socket being connected withthe surface heating unit by electric wiring as described hereinafter. Inthe socket a plug 12 with a flexible extension cable 13 has beeninserted, the latter serving as a connection to a source of electriccurrent.

FIG. 2 illustrates a battery-powered embodiment of the invention. Thetransverse rods 2 of the chair are of hollow cylindrical shape and serveto receive the battery, e.g., the cell 3.

The principal component of the heating arrangement is the surfaceheating unit 4, which is shown in FIG. 3. It can advantageously consistof a carrier material consisting of a synthetic material, e.g. Teflon,which has been treated to be heat conductive. Suitable techniques andcompositions for this purpose have been reported in the literature andpublished patents. See for example, Swiss Pat. No. 456,741 as showntherein, the resistance material can preferably be made from nonpolarplastic materials including polyolefins, e.g., polypropylene,polyethylene, polybutene or mixtures thereof. Polyvinylchloride andlupolen can also be used. Dispersed in the nonconductive component maybe graphite or carbon black. The surface heating unit is flexible andpreferably substantially coextensive with the entire reclining surfaceor actually constitutes the reclining surface.

As current conducting materials one can use in addition to glass fibers,jute or muslin weavings, also sheets or weavings of artificial materialssuch as Diolen or Nylon. These conductive cloths and sheets generallyexhibit a strong positive temperature coefficient of electricalresistance, so that current limiting occurs with increased heat andthere is no primary dependence on external heat controls such asthermostats and the like. With the use of such surface heating units thedanger of overheating is therefore avoided. In addition, they areinsensitive to humidity and water.

The resistance value of these conductive layers may be selected suchthat the heating can be carried out with voltages not exceeding lethalvalues, e.g., voltages less than 65 volts. ln this case the specialprecautions required to avoid shock are not necessary. For energizingthe heater, one can employ alternating current via stepdown transformers(e.g., one which reduces the mains voltage to say 42 volts), or directcurrent, from batteries e.g. cells supplying 6, 12 or 24 volts. Tosimplify electric connection with the surface heating unit 4, one canand surface heating unit;

deposit the contact strips 5, as shown in FIG. 3, alongside the surfaceheating unit. This may be done for example by spraying copper to formthe contacts. With these contact strips one can achieve an evendistribution of current over the complete surface. Alternatively, thecontact strips can be disposed over the broadside of the surface.

The current conductor wires 6 are welded or soldered to the contactstrips 5 or connected thereto by using appropriate connectors. The wires6 are connected in turn to the socket 7. Should a low voltage berequired (preferably no more than 65 volts) a suitable socket of specialconfiguration must be provided which will not receive the customary linevoltage plugs. lf batteries are used, they can be placed on theunderside of the chair, e.g., in the hollow transverse rod 2.

FIG. 4 illustrates a cross section of the finished reclining structure.Woven into the surface heating unit 4, which in this case is constructedfrom fabric, are copper wires 8 disposed in the selvedge to improveconductivity to the contact strips 5. if the deck chair requires avoltage over say 65 volts (e.g. line voltages) then the surface heatingunit is covered with insulating material 9.

To reduce the heat loss at the underside of the reclining section asmuch as possible, the heat-insulating layer 10 is provided. in this caseit consists of a synthetic material e.g., a coating of PVC or epoxyresin affixed to a rough aluminum foil heat reflector 11. The insulator10 and the foil 11, the surface heating unit 4, and insulating layers 9,are encapsulated in the fabric sections 1, which forms the actualreclining surface of the deck chair.

It has been established that chairs according to the invention requirevery little electric power. Generally one needs less than 30 watts ofpower. The chair is particularly effective for use on cold, sunny winterdays. The user of the deck chair is exposed in this event to the warmsun energy on one side and the warmth of the reclining section of thedeck chair on the other.

The invention is not to be limited to the specific examples shown and isadaptable to other seats as well including garden chairs or benches,Hollywood swings, hammocks, car seats, chair lifts and the like.

What is claimed is:

1. An article of furniture comprising a body support having a pluralityof longitudinal members arranged to for man open frame, and a recliningsection connected to said frame to provide a seating area within theframe, said reclining section including a reclining surface having aflexible heating section which includes a layer of electricallyconductive heating material with integral temperature-responsivedistributed current-limiting means, insulation means for electricallyinsulating said layer of heating material, and electrical contact meansconnected to said heating material for supplying a voltage to saidmaterial whereby said reclining section is electrically heated, saidcurrent-limiting means comprise a material having a positive temperaturecoefficient of electrical resistance.

2. An article offurniture as defined in claim 1, in which said heatingsurface has a value of resistivity selected to provide a suitable heatoutput when energized by voltages of less than lethal value.

3. An article of furniture as defined in claim 1, in which said heatingsurface includes a layer of spray-deposited electrical contact materialconnected to said heating material.

4. An article of furniture as defined in claim 1, in which said layer ofheating material comprises a unitary flexible plastic sheet occupying asubstantial part of said reclining section.

5. An article of furniture as defined in claim I, in which said layer ofheating material constitutes a principal load-supporting componentofsaid reclining flexible section.

a i t

1. An article of furniture comprising a body support having a plurality of longitudinal members arranged to form an open frame, and a reclining section connected to said frame to provide a seating area within the frame, said reclining section including a reclining surface having a flexible heating section which includes a layer of electrically conductive heating material with integral temperature-responsive distributed current-limiting means, insulation means for electrically insulating said layer of heating material, and electrical contact means connected to said heating material for supplying a voltage to said material whereby said reclining section is electrically heated, said currentlimiting means comprise a material having a positive temperature coefficient of electrical resistance.
 2. An article of furniture as defined in claim 1, in which said heating surface has a value of resistivity selected to provide a suitable heat output when energized by voltages of less than lethal value.
 3. An article of furniture as defined in claim 1, in which said heating surface includes a layer of spray-deposited electrical contact material connected to said heating material.
 4. An article of furniture as defined in claim 1, in which said layer of heating material comprises a unitary flexible plastic sheet occupying a substantial part of said reclining section.
 5. An article of furniture as defined in claim 1, in which said layer of heating material constitutes a principal load-supporting component of said reclining flexible section. 